An electromagnetically actuatable fuel injection valve, which has an axially movable valve needle as the closure element support for a spherical valve closure element, is described in German Patent Application No. 33 18 486. With a lower end region, the closure element support fits only partially around the valve closure elements, such that the enclosed region of the valve closure element extends at most only to its greatest diameter. The opening width of the recess receiving the valve closure element in the end region of the closure element support perpendicular to the longitudinal valve axis is thus at least as great as the greatest diameter of the valve closure element. A direct joining method, for example welding, soldering, or adhesive bonding, must be used to prevent the valve closure element from slipping out of the recess. If the recess and the valve closure element have the dimensions of a press fit, the valve closure element can also be retained by being pressed into the closure element support.
German Patent Application No. 195 03 224 describes an electromagnetically actuatable injection valve which has a valve needle whose closure element support, serving as the connecting part, is shaped from plastic. The spherical valve closure element and the closure element support are immovably joined to one another via a snap connection, the closure element support possessing resilient retaining jaws which fit around the valve closure element.
It has been known for some time, as is also evident from German Patent Application No. 40 08 675, to achieve immovable joins between individual components of valve needles in direct fashion, for example using weld beads.
Also known, from German Patent Application No. 38 08 635, is a fuel injection apparatus which has a valve needle having external helical grooves. The grooves delimited in the valve element form helical fuel channels which not only impart a swirl to the fuel, but also control the fuel flow velocity.